If you gonna play the 3 games I can give some advice and some sadnews.
DAO is the oldest but works quite well on Linux, not a single problem.
DA2 need the fucking EA App crap bullshit to run, even on steam. Because of that crap I had a lot of problems with alt + tab, crashings, resolutions bug. To fix it I need to enable virtual desktop in the wineprefix with my monitor resolution, after that everything went smooth.
DAI again the stupid fuck EA App. If you are in the same situation than me: bought the game on Origin, not on steam, I have some bad news about mods. FrostyMods just doesn’t work and is the EA bullshit problem. With the steam version someone made a patch for linux and looks like it works.